Electric safety switch



Jan. 3, 1928.

W. C. DAVIS, JR

ELECTRIC SAFETY SWITCH Filed March 18, 1927 gwuanto'c which the switch point is locked in closed p;

Patented Jan. 3, 1928.

PATENT 0F WILLIAM 0. avis, an, or aasrnn, ALAB M ELECTRIC SAFETY SWITCH.

Application filed March 18, 1927. Serial No. 176,477.

"Ihis-invention relates to an electric safety switch, and particularly to a construction in sition and electrically released therefrom by a circuit contact ata removed point ofcontrol. Y Q

In the electric control of safety switches I have found it very desirable to employ an elec r a y ac u t a ch lock. and t0; effect the shifting of'the switch point by supplemental meansafter the release of the latch. To accomplish this result I provide a latch member disposed to positively engage the movable switch point and adapted to be electrically released "therefrom by a magnet member so as to leave the point freefor opening movement which may be accomplished by a spring or other devices.

In such a construction it is further desirable that when the switch point is. forced to closed position by engagement with a wheel flange, the latch should automatically engage and hold. the point independent of any electrical action. A construction is thus pro- Vided by which the momentary energizing of the controlling magnet effects a release of the switch point and the further movements thereof are automatically effected so that it is not necessary to depend'uponelectric devices for shifting the point and restoring it to closed position. i

The invention has for an object toprovide a novel and improved construction of electric safety switch in'which a movable memher is engaged by a latch by which it is held in closed position andsuch latch is adapted to be actuated by a magnet for releasing its engagement with the movable switch member or point. i A further object of the invention is to provide tension means by whichflt-he switch point will be automatically shifted into open posi tion and the latch restored to its engaging position with said pointwhen closed. Another object of the invention is {to provide a simple and efiicient construction of electrically actuated latch adapted for appli- Cati n to a saf y, s ch to er ontrolled by a tr n. de c a ap ed to e abl s c rcuit t the actuating magnet of the switch.

Other and further objects and advantages of the invention will be hereinafter set forth and the novel features thereof defined by the appended claims. 7 H I In the accompanying drawing:

p i d; a

Figure 2 is-a detail perspective of the switch point and latch; i

Figure 3 is a detail section of the point in closed position; and

Figure 4 is a modifiedform of the invention. i

Like reference characters designate corre-. sponding parts throughout the several fig: ures of the drawing'. p i

This construction of safety switch is adapted for various applications but is par ticularly designed for use in connection with safety switch systems such as showninm-y copending application filed of even date herewith. In the application. of the invention shown in Figure 1 the numeral 10 (less ignates the main line rails and 11 the rails or tracks of asiding havingswitchconnec tion therewith. This switch comprises a Figure 1 a plan showing the switch and tensioned into openposition bya spring 14 or other suitable means. The switch point 12 is provided with an aperture 15 the rear wall 16 of which is adapted to cooperate'with a latch 17 whichma'y'be ofhooked construction as shown. This latch is pivotally mounted at 18 upona suitable support and formed with an armature face 19 which cooperates with an electro-magnet 20 having circuit connections 21 extending therefrom. These connections are intended to cooperate with a third rail and the track-rails as shown in my application aforesaid and circuit established by a train controlled device as s cwn n a d ppl c t In order to throw th-e latchinto engaging position with the switch point when the magnet is not energized, aspring 22 may be extended t ere t a ed m and the yariou s partsof the latch mechanism are adapted to be enclosed by a suitable casing as ind cflt det g n igureby whih l eyiar Pr t c ed f om di a d m u o' lnsi r th ir contin e fl cient'cpe onl In Figure 4: a modifiedgform of the invention is b own. inwhich the switch point 12 is positively actuated into Open position through the controlling magnet for the latc earl-the e h d y p n s In t f rm o the i en on the latch 25 s provided. with a hack d e idv 25 n ng; t wall 16 pf theope ing 15in the point 12 and" is pivotally mounted at 27 fromwhich lee.

movable point '12 pivotally mounted at 18 point a crank arm 28 carries a pusher bar 29 slidingly mounted thereon by means of the slot 30 operating upon the pin 31 of the cranl: arm 28. Theinner end of the push bar 29 is formed with a lateral arm 32 from which a tension spring 38 extends to the crank arm 28. The opposite end of the bar 29 passes through a guide 34 and engages the body oi the switch point 12. For the purpose of actuating the latch to release the same magnet 35 is provided and the solenoid 3-6 therefrom has a loose pivotal connection with the latch at 37 to provide for the arc-uate movement of the latch and the rectilinear moven'ient ot' the solenoid. The latch is normally tensioned into engaging position with the point by a spring member 38 surrounding the solenoid and extending between the magnet and a coller 39011 the solenoid. This solenoid. is suitably guided in its movement by means of a rod 40 as shown in Figure i.

In the operation of this form of the invention the initial movement of the soleno d releases the latch and the crank arm thereof has an idle movement upon the pusher bar until such release is effected and thereafter actuates the pusher bar to positively throw the switch. In the closing of the switch by contact with the wheel flange of a train the bar is first actuated and by its pressure upon the crank a m of the latch insures a positive actuation thereof into engagement with the point in the event that the spring provided for that purpose is not sufficient. In both forms of the invention the hooked end of the latch has an inclined face ll'which enthe all 16 of the aperture in the switch point and forces the latch away from said wall suliiciently to permit the closing of the point.

The operation of the invention will be ap parent from the foregoing description from which it willbe seen that the switch point is normally held in locked position and cannot be released theretrom except through a circuit established in the magnet controlling one movement of the latch, and after such release the switch point is thrown to its open position by supplemental means. Under such a construction it is only necessary to provide suflicient current to actuate the latch as its releasing movement and the opening of the switch may be effected by other means. This avoids the necessity of any complicated electrical connections for operating the switch point and provides a a simple, efficient and economically constructed controlling device for the switch.

While the details of construction have been shown and described, the invention is not confined thereto as changes and alterations may be made therein within the spirit 'to extend through said aperture and eng e of the invention as defined by the following claims. Q-

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States, is

Lin an electric safety switch, a movable rail member, a latch disposed to directly engage said member, and an electrically actuated magnet arranged to release said latch.

2. In an electric safety switch. a movable rail mem er. a latch disposed to directly engage said member, an electrically actuated magnet associated .ith the latch and rail member to release saidlatch, and tension means for shifting said movable member when released by said magnet.

In an electric safety switch, a movable rail member, a latch disposed to directly engage said member, an electrically actuated magnet arranged to release said latch, and tension means connected to restore said latch to engaging position when the magnet is not energized to permit its automatic engagement witl the rail member.

4. In an electric safety switch, a movable switch point, a pivoted latch adapted to directly engage and retain the same in closed position, an electrically energized magnet device cooperating with said latch to release the sameYlrom engagement with said point, and tension means extending from said latch to restore the same to engaging position.

In "an electric safety switch, a movable switch point, a pivoted latch adapted to directly engage and retain the same in closed position, an electrically energized magnet device cooperating with said latch to release the same from engagement with said point, tension means extending from said latch to restore the same to engaging position with said point,and a tension spring extending from said switch point to automatically open the same when released.

6. In an electric safety switch. a pivoted switch point having an aperture therein, a latch member having a hooked end adapted a *all thereof, a magnetically attrabted member carried by said latch, and a magnet cooperating with said member to shift the latch to released position.

7. In an electric safety switch, a pivoted switch point having an aperture there through, a pivoted latch having a h'oolted head adapted to engage a wall of said aperture and an inclined outer face adapted to be engaged by said point, a tension spring extending from said latch to a fixed point for restoring the same, and a magnet member disposed to attract and shift said-latch to it released position.

In testimony whereoi l afliX my signature.

WILLIAM C. DAVIS, JR. 

